In keeping with the idea that I will be using the WRG rules as much as possible, here are my current thoughts on combat.
Hand to hand combat: In a period (30 seconds), each figure involved generates a casualty total in the normal manner. Individual figures will not be rated as LI, except for special cases listed later (and mostly dealing with missile combat). Casualty totals are compared, and the higher total does a wound to the opponent. Determine the nature of the wound by rolling a normal six-sided die for each casualty above the opponent's total and compare to a chart (hit locations? possibly as an optional rule). For multiple combatants, first pair off combatants, with any excess on one side divided up according to a method that takes into account nominal base sizes in the WRG rules (that is, larger base sizes can be attacked by more figures of smaller base size). In a fight with more than one combatant on one side, all combatants on that side generate casualty totals, each using a different random factor roll, which are added together and compared to the total on the other side. If the single figure gets a higher total, all of the figures opposing it might be wounded. Use a modification of the "Risk to the general" rules: for each figure, roll a die (regular six-sided die for "Enthusiastic", averaging die for "Disciplined") and multiply by the excess number of casualties. If the result is greater than the total number of figures fighting against the opposing figure, the figure takes a wound based on the amount of excess casualties. (Example: Abel and Beth are fighting against Xavier. Abel generates 1 casualty, Beth generates 2, for a total of 3 on their side. Xavier generates an astounding 4. Abel and Beth roll dice, with a result of 3 or higher, since the die is multiplied by the excess casualties of 1 and, since there are two of them, the total must be 3 or more, indicating that they take a wound of 1 die in value on the wound chart. If Abel or Beth are "Disciplined", they will take a wound on a roll of 3 or higher, escaping injury 1 chance in 6, while if either is "Enthusiastic", they can escape wounding 2 chances in 6.) Edited to add: If a figure that rates as a model (elephant, chariot, or artillery, or anything that is treated as one of those, such as dragons) in the regular game is fighting against a figure that is normal, but has no armor, then count the normal figure as LI instead of LMI/MI.
Missile combat: This will have the biggest changes. When firing a missile weapon, first determine initiative by rolling a die (type based on "Disciplined" or "Enthusiastic"). The firer with initiative fires first, then the next firer, and so on (any ties roll off). The firer will generate a casualty total and so will the target (using regular hand-to-hand random factors, not the special missile ones of the basic WRG rules). The target's total will be based on a base factor of 1, while the firer's will be based on either a target that is LI (LC if mounted), or the actual target type, whichever is better for the target. The firer will cause a wound based on excess casualties.
Wounds: The lightest wounds will actually be a "recoil" result, which means that the "wounded" figure will attempt to disengage from combat. The opponent may choose to press, which will allow the charge bonus in the next turn but risks being flanked by unengaged opponents, or to let the figure disengage.
Combat sequence: The basic combat sequence will be something like 1) Check morale of all non-player figures that need to do so; 2) Referee adjudicates maneuvers of unengaged figures; 3) Determine initiative for missile fire; 4) Missile fire in order of initiative; 5) Hand to hand combat.
Mounted figures: I still need to think about this, but currently I am thinking that, for horse/camel-sized mounts, a wound has a 50/50 chance of going to the mount or the figure.